Modelling of heat transfer in waterjet guided laser drilling of silicon

Waterjet guided laser processing is an Internationally patented technique based on guiding a laser beam inside a thin, high-speed waterjet. The process combines the advantages of laser processing with those of waterjet cutting. It is very suitable in processing thin and beat-sensitive materials with a high degree of precision required. A model and simulation method for waterjet guided laser drilling on a silicon substrate are presented in this study. A finite difference method has been developed to simulate the thermal field and phase changes involved. The model represents the thermal process in detail. The simulation results predict the main characteristics of waterjet guided laser drilling. The study gives insight into the interactions between the laser beam, waterjet and workpiece material during drilling of a silicon substrate.